This prepares for compiling out vfio group after vfio device cdev is added. No vfio_group decode code should be in vfio_main.c, and neither device->group reference should be in vfio_main.c. No functional change is intended. Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx> --- drivers/vfio/Makefile | 1 + drivers/vfio/group.c | 877 +++++++++++++++++++++++++++++++++++++++ drivers/vfio/vfio.h | 22 + drivers/vfio/vfio_main.c | 877 +-------------------------------------- 4 files changed, 907 insertions(+), 870 deletions(-) create mode 100644 drivers/vfio/group.c diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile index b953517dc70f..3783db7e8082 100644 --- a/drivers/vfio/Makefile +++ b/drivers/vfio/Makefile @@ -4,6 +4,7 @@ vfio_virqfd-y := virqfd.o obj-$(CONFIG_VFIO) += vfio.o vfio-y += vfio_main.o \ + group.o \ iova_bitmap.o vfio-$(CONFIG_IOMMUFD) += iommufd.o vfio-$(CONFIG_VFIO_CONTAINER) += container.o diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c new file mode 100644 index 000000000000..c5d8bf10495e --- /dev/null +++ b/drivers/vfio/group.c @@ -0,0 +1,877 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VFIO core + * + * Copyright (C) 2012 Red Hat, Inc. All rights reserved. + * Author: Alex Williamson <alex.williamson@xxxxxxxxxx> + * + * Derived from original vfio: + * Copyright 2010 Cisco Systems, Inc. All rights reserved. + * Author: Tom Lyon, pugs@xxxxxxxxx + */ + +#include <linux/vfio.h> +#include <linux/iommufd.h> +#include <linux/anon_inodes.h> +#include "vfio.h" + +static struct vfio { + struct class *class; + struct list_head group_list; + struct mutex group_lock; /* locks group_list */ + struct ida group_ida; + dev_t group_devt; +} vfio; + +static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group, + char *buf) +{ + struct vfio_device *it, *device = ERR_PTR(-ENODEV); + + mutex_lock(&group->device_lock); + list_for_each_entry(it, &group->device_list, group_next) { + int ret; + + if (it->ops->match) { + ret = it->ops->match(it, buf); + if (ret < 0) { + device = ERR_PTR(ret); + break; + } + } else { + ret = !strcmp(dev_name(it->dev), buf); + } + + if (ret && vfio_device_try_get_registration(it)) { + device = it; + break; + } + } + mutex_unlock(&group->device_lock); + + return device; +} + +/* + * VFIO Group fd, /dev/vfio/$GROUP + */ +static bool vfio_group_has_iommu(struct vfio_group *group) +{ + lockdep_assert_held(&group->group_lock); + /* + * There can only be users if there is a container, and if there is a + * container there must be users. + */ + WARN_ON(!group->container != !group->container_users); + + return group->container || group->iommufd; +} + +/* + * VFIO_GROUP_UNSET_CONTAINER should fail if there are other users or + * if there was no container to unset. Since the ioctl is called on + * the group, we know that still exists, therefore the only valid + * transition here is 1->0. + */ +static int vfio_group_ioctl_unset_container(struct vfio_group *group) +{ + int ret = 0; + + mutex_lock(&group->group_lock); + if (!vfio_group_has_iommu(group)) { + ret = -EINVAL; + goto out_unlock; + } + if (group->container) { + if (group->container_users != 1) { + ret = -EBUSY; + goto out_unlock; + } + vfio_group_detach_container(group); + } + if (group->iommufd) { + iommufd_ctx_put(group->iommufd); + group->iommufd = NULL; + } + +out_unlock: + mutex_unlock(&group->group_lock); + return ret; +} + +static int vfio_group_ioctl_set_container(struct vfio_group *group, + int __user *arg) +{ + struct vfio_container *container; + struct iommufd_ctx *iommufd; + struct fd f; + int ret; + int fd; + + if (get_user(fd, arg)) + return -EFAULT; + + f = fdget(fd); + if (!f.file) + return -EBADF; + + mutex_lock(&group->group_lock); + if (vfio_group_has_iommu(group)) { + ret = -EINVAL; + goto out_unlock; + } + if (!group->iommu_group) { + ret = -ENODEV; + goto out_unlock; + } + + container = vfio_container_from_file(f.file); + if (container) { + ret = vfio_container_attach_group(container, group); + goto out_unlock; + } + + iommufd = iommufd_ctx_from_file(f.file); + if (!IS_ERR(iommufd)) { + u32 ioas_id; + + ret = iommufd_vfio_compat_ioas_id(iommufd, &ioas_id); + if (ret) { + iommufd_ctx_put(group->iommufd); + goto out_unlock; + } + + group->iommufd = iommufd; + goto out_unlock; + } + + /* The FD passed is not recognized. */ + ret = -EBADFD; + +out_unlock: + mutex_unlock(&group->group_lock); + fdput(f); + return ret; +} + +static int vfio_device_group_open(struct vfio_device *device) +{ + int ret; + + mutex_lock(&device->group->group_lock); + if (!vfio_group_has_iommu(device->group)) { + ret = -EINVAL; + goto out_unlock; + } + + /* + * Here we pass the KVM pointer with the group under the lock. If the + * device driver will use it, it must obtain a reference and release it + * during close_device. + */ + ret = vfio_device_open(device, device->group->iommufd, + device->group->kvm); + +out_unlock: + mutex_unlock(&device->group->group_lock); + return ret; +} + +void vfio_device_group_close(struct vfio_device *device) +{ + mutex_lock(&device->group->group_lock); + vfio_device_close(device, device->group->iommufd); + mutex_unlock(&device->group->group_lock); +} + +static struct file *vfio_device_open_file(struct vfio_device *device) +{ + struct file *filep; + int ret; + + ret = vfio_device_group_open(device); + if (ret) + goto err_out; + + /* + * We can't use anon_inode_getfd() because we need to modify + * the f_mode flags directly to allow more than just ioctls + */ + filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops, + device, O_RDWR); + if (IS_ERR(filep)) { + ret = PTR_ERR(filep); + goto err_close_device; + } + + /* + * TODO: add an anon_inode interface to do this. + * Appears to be missing by lack of need rather than + * explicitly prevented. Now there's need. + */ + filep->f_mode |= (FMODE_PREAD | FMODE_PWRITE); + + if (device->group->type == VFIO_NO_IOMMU) + dev_warn(device->dev, "vfio-noiommu device opened by user " + "(%s:%d)\n", current->comm, task_pid_nr(current)); + /* + * On success the ref of device is moved to the file and + * put in vfio_device_fops_release() + */ + return filep; + +err_close_device: + vfio_device_group_close(device); +err_out: + return ERR_PTR(ret); +} + +static int vfio_group_ioctl_get_device_fd(struct vfio_group *group, + char __user *arg) +{ + struct vfio_device *device; + struct file *filep; + char *buf; + int fdno; + int ret; + + buf = strndup_user(arg, PAGE_SIZE); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + device = vfio_device_get_from_name(group, buf); + kfree(buf); + if (IS_ERR(device)) + return PTR_ERR(device); + + fdno = get_unused_fd_flags(O_CLOEXEC); + if (fdno < 0) { + ret = fdno; + goto err_put_device; + } + + filep = vfio_device_open_file(device); + if (IS_ERR(filep)) { + ret = PTR_ERR(filep); + goto err_put_fdno; + } + + fd_install(fdno, filep); + return fdno; + +err_put_fdno: + put_unused_fd(fdno); +err_put_device: + vfio_device_put_registration(device); + return ret; +} + +static int vfio_group_ioctl_get_status(struct vfio_group *group, + struct vfio_group_status __user *arg) +{ + unsigned long minsz = offsetofend(struct vfio_group_status, flags); + struct vfio_group_status status; + + if (copy_from_user(&status, arg, minsz)) + return -EFAULT; + + if (status.argsz < minsz) + return -EINVAL; + + status.flags = 0; + + mutex_lock(&group->group_lock); + if (!group->iommu_group) { + mutex_unlock(&group->group_lock); + return -ENODEV; + } + + /* + * With the container FD the iommu_group_claim_dma_owner() is done + * during SET_CONTAINER but for IOMMFD this is done during + * VFIO_GROUP_GET_DEVICE_FD. Meaning that with iommufd + * VFIO_GROUP_FLAGS_VIABLE could be set but GET_DEVICE_FD will fail due + * to viability. + */ + if (vfio_group_has_iommu(group)) + status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET | + VFIO_GROUP_FLAGS_VIABLE; + else if (!iommu_group_dma_owner_claimed(group->iommu_group)) + status.flags |= VFIO_GROUP_FLAGS_VIABLE; + mutex_unlock(&group->group_lock); + + if (copy_to_user(arg, &status, minsz)) + return -EFAULT; + return 0; +} + +static long vfio_group_fops_unl_ioctl(struct file *filep, + unsigned int cmd, unsigned long arg) +{ + struct vfio_group *group = filep->private_data; + void __user *uarg = (void __user *)arg; + + switch (cmd) { + case VFIO_GROUP_GET_DEVICE_FD: + return vfio_group_ioctl_get_device_fd(group, uarg); + case VFIO_GROUP_GET_STATUS: + return vfio_group_ioctl_get_status(group, uarg); + case VFIO_GROUP_SET_CONTAINER: + return vfio_group_ioctl_set_container(group, uarg); + case VFIO_GROUP_UNSET_CONTAINER: + return vfio_group_ioctl_unset_container(group); + default: + return -ENOTTY; + } +} + +static int vfio_group_fops_open(struct inode *inode, struct file *filep) +{ + struct vfio_group *group = + container_of(inode->i_cdev, struct vfio_group, cdev); + int ret; + + mutex_lock(&group->group_lock); + + /* + * drivers can be zero if this races with vfio_device_remove_group(), it + * will be stable at 0 under the group rwsem + */ + if (refcount_read(&group->drivers) == 0) { + ret = -ENODEV; + goto out_unlock; + } + + if (group->type == VFIO_NO_IOMMU && !capable(CAP_SYS_RAWIO)) { + ret = -EPERM; + goto out_unlock; + } + + /* + * Do we need multiple instances of the group open? Seems not. + */ + if (group->opened_file) { + ret = -EBUSY; + goto out_unlock; + } + group->opened_file = filep; + filep->private_data = group; + ret = 0; +out_unlock: + mutex_unlock(&group->group_lock); + return ret; +} + +static int vfio_group_fops_release(struct inode *inode, struct file *filep) +{ + struct vfio_group *group = filep->private_data; + + filep->private_data = NULL; + + mutex_lock(&group->group_lock); + /* + * Device FDs hold a group file reference, therefore the group release + * is only called when there are no open devices. + */ + WARN_ON(group->notifier.head); + if (group->container) + vfio_group_detach_container(group); + if (group->iommufd) { + iommufd_ctx_put(group->iommufd); + group->iommufd = NULL; + } + group->opened_file = NULL; + mutex_unlock(&group->group_lock); + return 0; +} + +static const struct file_operations vfio_group_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = vfio_group_fops_unl_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .open = vfio_group_fops_open, + .release = vfio_group_fops_release, +}; + +/* + * Group objects - create, release, get, put, search + */ +static struct vfio_group * +vfio_group_find_from_iommu(struct iommu_group *iommu_group) +{ + struct vfio_group *group; + + lockdep_assert_held(&vfio.group_lock); + + /* + * group->iommu_group from the vfio.group_list cannot be NULL + * under the vfio.group_lock. + */ + list_for_each_entry(group, &vfio.group_list, vfio_next) { + if (group->iommu_group == iommu_group) + return group; + } + return NULL; +} + +static void vfio_group_release(struct device *dev) +{ + struct vfio_group *group = container_of(dev, struct vfio_group, dev); + + mutex_destroy(&group->device_lock); + mutex_destroy(&group->group_lock); + WARN_ON(group->iommu_group); + ida_free(&vfio.group_ida, MINOR(group->dev.devt)); + kfree(group); +} + +static struct vfio_group *vfio_group_alloc(struct iommu_group *iommu_group, + enum vfio_group_type type) +{ + struct vfio_group *group; + int minor; + + group = kzalloc(sizeof(*group), GFP_KERNEL); + if (!group) + return ERR_PTR(-ENOMEM); + + minor = ida_alloc_max(&vfio.group_ida, MINORMASK, GFP_KERNEL); + if (minor < 0) { + kfree(group); + return ERR_PTR(minor); + } + + device_initialize(&group->dev); + group->dev.devt = MKDEV(MAJOR(vfio.group_devt), minor); + group->dev.class = vfio.class; + group->dev.release = vfio_group_release; + cdev_init(&group->cdev, &vfio_group_fops); + group->cdev.owner = THIS_MODULE; + + refcount_set(&group->drivers, 1); + mutex_init(&group->group_lock); + INIT_LIST_HEAD(&group->device_list); + mutex_init(&group->device_lock); + group->iommu_group = iommu_group; + /* put in vfio_group_release() */ + iommu_group_ref_get(iommu_group); + group->type = type; + BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier); + + return group; +} + +static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group, + enum vfio_group_type type) +{ + struct vfio_group *group; + struct vfio_group *ret; + int err; + + lockdep_assert_held(&vfio.group_lock); + + group = vfio_group_alloc(iommu_group, type); + if (IS_ERR(group)) + return group; + + err = dev_set_name(&group->dev, "%s%d", + group->type == VFIO_NO_IOMMU ? "noiommu-" : "", + iommu_group_id(iommu_group)); + if (err) { + ret = ERR_PTR(err); + goto err_put; + } + + err = cdev_device_add(&group->cdev, &group->dev); + if (err) { + ret = ERR_PTR(err); + goto err_put; + } + + list_add(&group->vfio_next, &vfio.group_list); + + return group; + +err_put: + put_device(&group->dev); + return ret; +} + +static struct vfio_group *vfio_noiommu_group_alloc(struct device *dev, + enum vfio_group_type type) +{ + struct iommu_group *iommu_group; + struct vfio_group *group; + int ret; + + iommu_group = iommu_group_alloc(); + if (IS_ERR(iommu_group)) + return ERR_CAST(iommu_group); + + ret = iommu_group_set_name(iommu_group, "vfio-noiommu"); + if (ret) + goto out_put_group; + ret = iommu_group_add_device(iommu_group, dev); + if (ret) + goto out_put_group; + + mutex_lock(&vfio.group_lock); + group = vfio_create_group(iommu_group, type); + mutex_unlock(&vfio.group_lock); + if (IS_ERR(group)) { + ret = PTR_ERR(group); + goto out_remove_device; + } + iommu_group_put(iommu_group); + return group; + +out_remove_device: + iommu_group_remove_device(dev); +out_put_group: + iommu_group_put(iommu_group); + return ERR_PTR(ret); +} + +static bool vfio_group_has_device(struct vfio_group *group, struct device *dev) +{ + struct vfio_device *device; + + mutex_lock(&group->device_lock); + list_for_each_entry(device, &group->device_list, group_next) { + if (device->dev == dev) { + mutex_unlock(&group->device_lock); + return true; + } + } + mutex_unlock(&group->device_lock); + return false; +} + +static struct vfio_group *vfio_group_find_or_alloc(struct device *dev) +{ + struct iommu_group *iommu_group; + struct vfio_group *group; + + iommu_group = iommu_group_get(dev); + if (!iommu_group && vfio_noiommu) { + /* + * With noiommu enabled, create an IOMMU group for devices that + * don't already have one, implying no IOMMU hardware/driver + * exists. Taint the kernel because we're about to give a DMA + * capable device to a user without IOMMU protection. + */ + group = vfio_noiommu_group_alloc(dev, VFIO_NO_IOMMU); + if (!IS_ERR(group)) { + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + dev_warn(dev, "Adding kernel taint for vfio-noiommu group on device\n"); + } + return group; + } + + if (!iommu_group) + return ERR_PTR(-EINVAL); + + /* + * VFIO always sets IOMMU_CACHE because we offer no way for userspace to + * restore cache coherency. It has to be checked here because it is only + * valid for cases where we are using iommu groups. + */ + if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) { + iommu_group_put(iommu_group); + return ERR_PTR(-EINVAL); + } + + mutex_lock(&vfio.group_lock); + group = vfio_group_find_from_iommu(iommu_group); + if (group) { + if (WARN_ON(vfio_group_has_device(group, dev))) + group = ERR_PTR(-EINVAL); + else + refcount_inc(&group->drivers); + } else { + group = vfio_create_group(iommu_group, VFIO_IOMMU); + } + mutex_unlock(&vfio.group_lock); + + /* The vfio_group holds a reference to the iommu_group */ + iommu_group_put(iommu_group); + return group; +} + +int vfio_device_set_group(struct vfio_device *device, + enum vfio_group_type type) +{ + struct vfio_group *group; + + if (type == VFIO_IOMMU) + group = vfio_group_find_or_alloc(device->dev); + else + group = vfio_noiommu_group_alloc(device->dev, type); + + if (IS_ERR(group)) + return PTR_ERR(group); + + /* Our reference on group is moved to the device */ + device->group = group; + return 0; +} + +void vfio_device_remove_group(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + struct iommu_group *iommu_group; + + if (group->type == VFIO_NO_IOMMU || group->type == VFIO_EMULATED_IOMMU) + iommu_group_remove_device(device->dev); + + /* Pairs with vfio_create_group() / vfio_group_get_from_iommu() */ + if (!refcount_dec_and_mutex_lock(&group->drivers, &vfio.group_lock)) + return; + list_del(&group->vfio_next); + + /* + * We could concurrently probe another driver in the group that might + * race vfio_device_remove_group() with vfio_get_group(), so we have to + * ensure that the sysfs is all cleaned up under lock otherwise the + * cdev_device_add() will fail due to the name aready existing. + */ + cdev_device_del(&group->cdev, &group->dev); + + mutex_lock(&group->group_lock); + /* + * These data structures all have paired operations that can only be + * undone when the caller holds a live reference on the device. Since + * all pairs must be undone these WARN_ON's indicate some caller did not + * properly hold the group reference. + */ + WARN_ON(!list_empty(&group->device_list)); + WARN_ON(group->notifier.head); + + /* + * Revoke all users of group->iommu_group. At this point we know there + * are no devices active because we are unplugging the last one. Setting + * iommu_group to NULL blocks all new users. + */ + if (group->container) + vfio_group_detach_container(group); + iommu_group = group->iommu_group; + group->iommu_group = NULL; + mutex_unlock(&group->group_lock); + mutex_unlock(&vfio.group_lock); + + iommu_group_put(iommu_group); + put_device(&group->dev); +} + +void vfio_device_group_register(struct vfio_device *device) +{ + mutex_lock(&device->group->device_lock); + list_add(&device->group_next, &device->group->device_list); + mutex_unlock(&device->group->device_lock); +} + +void vfio_device_group_unregister(struct vfio_device *device) +{ + mutex_lock(&device->group->device_lock); + list_del(&device->group_next); + mutex_unlock(&device->group->device_lock); +} + +int vfio_device_group_use_iommu(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + int ret = 0; + + lockdep_assert_held(&group->group_lock); + + if (WARN_ON(!group->container)) + return -EINVAL; + + ret = vfio_group_use_container(group); + if (ret) + return ret; + vfio_device_container_register(device); + return 0; +} + +void vfio_device_group_unuse_iommu(struct vfio_device *device) +{ + struct vfio_group *group = device->group; + + lockdep_assert_held(&group->group_lock); + + if (WARN_ON(!group->container)) + return; + + vfio_device_container_unregister(device); + vfio_group_unuse_container(group); +} + +bool vfio_device_has_container(struct vfio_device *device) +{ + return device->group->container; +} + +/** + * vfio_file_iommu_group - Return the struct iommu_group for the vfio group file + * @file: VFIO group file + * + * The returned iommu_group is valid as long as a ref is held on the file. This + * returns a reference on the group. This function is deprecated, only the SPAPR + * path in kvm should call it. + */ +struct iommu_group *vfio_file_iommu_group(struct file *file) +{ + struct vfio_group *group = file->private_data; + struct iommu_group *iommu_group = NULL; + + if (!IS_ENABLED(CONFIG_SPAPR_TCE_IOMMU)) + return NULL; + + if (!vfio_file_is_group(file)) + return NULL; + + mutex_lock(&group->group_lock); + if (group->iommu_group) { + iommu_group = group->iommu_group; + iommu_group_ref_get(iommu_group); + } + mutex_unlock(&group->group_lock); + return iommu_group; +} +EXPORT_SYMBOL_GPL(vfio_file_iommu_group); + +/** + * vfio_file_is_group - True if the file is usable with VFIO aPIS + * @file: VFIO group file + */ +bool vfio_file_is_group(struct file *file) +{ + return file->f_op == &vfio_group_fops; +} +EXPORT_SYMBOL_GPL(vfio_file_is_group); + +/** + * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file + * is always CPU cache coherent + * @file: VFIO group file + * + * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop + * bit in DMA transactions. A return of false indicates that the user has + * rights to access additional instructions such as wbinvd on x86. + */ +bool vfio_file_enforced_coherent(struct file *file) +{ + struct vfio_group *group = file->private_data; + struct vfio_device *device; + bool ret = true; + + if (!vfio_file_is_group(file)) + return true; + + /* + * If the device does not have IOMMU_CAP_ENFORCE_CACHE_COHERENCY then + * any domain later attached to it will also not support it. If the cap + * is set then the iommu_domain eventually attached to the device/group + * must use a domain with enforce_cache_coherency(). + */ + mutex_lock(&group->device_lock); + list_for_each_entry(device, &group->device_list, group_next) { + if (!device_iommu_capable(device->dev, + IOMMU_CAP_ENFORCE_CACHE_COHERENCY)) { + ret = false; + break; + } + } + mutex_unlock(&group->device_lock); + return ret; +} +EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); + +/** + * vfio_file_set_kvm - Link a kvm with VFIO drivers + * @file: VFIO group file + * @kvm: KVM to link + * + * When a VFIO device is first opened the KVM will be available in + * device->kvm if one was associated with the group. + */ +void vfio_file_set_kvm(struct file *file, struct kvm *kvm) +{ + struct vfio_group *group = file->private_data; + + if (!vfio_file_is_group(file)) + return; + + mutex_lock(&group->group_lock); + group->kvm = kvm; + mutex_unlock(&group->group_lock); +} +EXPORT_SYMBOL_GPL(vfio_file_set_kvm); + +/** + * vfio_file_has_dev - True if the VFIO file is a handle for device + * @file: VFIO file to check + * @device: Device that must be part of the file + * + * Returns true if given file has permission to manipulate the given device. + */ +bool vfio_file_has_dev(struct file *file, struct vfio_device *device) +{ + struct vfio_group *group = file->private_data; + + if (!vfio_file_is_group(file)) + return false; + + return group == device->group; +} +EXPORT_SYMBOL_GPL(vfio_file_has_dev); + +static char *vfio_devnode(struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev)); +} + +int __init vfio_group_init(void) +{ + int ret; + + ida_init(&vfio.group_ida); + mutex_init(&vfio.group_lock); + INIT_LIST_HEAD(&vfio.group_list); + + ret = vfio_container_init(); + if (ret) + return ret; + + /* /dev/vfio/$GROUP */ + vfio.class = class_create(THIS_MODULE, "vfio"); + if (IS_ERR(vfio.class)) { + ret = PTR_ERR(vfio.class); + goto err_group_class; + } + + vfio.class->devnode = vfio_devnode; + + ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK + 1, "vfio"); + if (ret) + goto err_alloc_chrdev; + return 0; + +err_alloc_chrdev: + class_destroy(vfio.class); + vfio.class = NULL; +err_group_class: + vfio_container_cleanup(); + return ret; +} + +void vfio_group_cleanup(void) +{ + WARN_ON(!list_empty(&vfio.group_list)); + ida_destroy(&vfio.group_ida); + unregister_chrdev_region(vfio.group_devt, MINORMASK + 1); + class_destroy(vfio.class); + vfio.class = NULL; + vfio_container_cleanup(); +} diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h index a112e8f2b291..2e05418fd18d 100644 --- a/drivers/vfio/vfio.h +++ b/drivers/vfio/vfio.h @@ -6,6 +6,7 @@ #ifndef __VFIO_VFIO_H__ #define __VFIO_VFIO_H__ +#include <linux/file.h> #include <linux/device.h> #include <linux/cdev.h> #include <linux/module.h> @@ -15,6 +16,15 @@ struct iommu_group; struct vfio_device; struct vfio_container; +void vfio_device_put_registration(struct vfio_device *device); +bool vfio_device_try_get_registration(struct vfio_device *device); +int vfio_device_open(struct vfio_device *device, + struct iommufd_ctx *iommufd, struct kvm *kvm); +void vfio_device_close(struct vfio_device *device, + struct iommufd_ctx *iommufd); + +extern const struct file_operations vfio_device_fops; + enum vfio_group_type { /* * Physical device with IOMMU backing. @@ -66,6 +76,18 @@ struct vfio_group { struct iommufd_ctx *iommufd; }; +int vfio_device_set_group(struct vfio_device *device, + enum vfio_group_type type); +void vfio_device_remove_group(struct vfio_device *device); +void vfio_device_group_register(struct vfio_device *device); +void vfio_device_group_unregister(struct vfio_device *device); +int vfio_device_group_use_iommu(struct vfio_device *device); +void vfio_device_group_unuse_iommu(struct vfio_device *device); +void vfio_device_group_close(struct vfio_device *device); +bool vfio_device_has_container(struct vfio_device *device); +int __init vfio_group_init(void); +void vfio_group_cleanup(void); + #if IS_ENABLED(CONFIG_VFIO_CONTAINER) /* events for the backend driver notify callback */ enum vfio_iommu_notify_type { diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 11fe044e8703..e89971651d34 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -13,8 +13,6 @@ #include <linux/cdev.h> #include <linux/compat.h> #include <linux/device.h> -#include <linux/file.h> -#include <linux/anon_inodes.h> #include <linux/fs.h> #include <linux/idr.h> #include <linux/iommu.h> @@ -43,17 +41,11 @@ #define DRIVER_DESC "VFIO - User Level meta-driver" static struct vfio { - struct class *class; - struct list_head group_list; - struct mutex group_lock; /* locks group_list */ - struct ida group_ida; - dev_t group_devt; struct class *device_class; struct ida device_ida; } vfio; static DEFINE_XARRAY(vfio_device_set_xa); -static const struct file_operations vfio_group_fops; int vfio_assign_device_set(struct vfio_device *device, void *set_id) { @@ -126,168 +118,17 @@ static void vfio_release_device_set(struct vfio_device *device) xa_unlock(&vfio_device_set_xa); } -/* - * Group objects - create, release, get, put, search - */ -static struct vfio_group * -vfio_group_find_from_iommu(struct iommu_group *iommu_group) -{ - struct vfio_group *group; - - lockdep_assert_held(&vfio.group_lock); - - /* - * group->iommu_group from the vfio.group_list cannot be NULL - * under the vfio.group_lock. - */ - list_for_each_entry(group, &vfio.group_list, vfio_next) { - if (group->iommu_group == iommu_group) - return group; - } - return NULL; -} - -static void vfio_group_release(struct device *dev) -{ - struct vfio_group *group = container_of(dev, struct vfio_group, dev); - - mutex_destroy(&group->device_lock); - mutex_destroy(&group->group_lock); - WARN_ON(group->iommu_group); - ida_free(&vfio.group_ida, MINOR(group->dev.devt)); - kfree(group); -} - -static struct vfio_group *vfio_group_alloc(struct iommu_group *iommu_group, - enum vfio_group_type type) -{ - struct vfio_group *group; - int minor; - - group = kzalloc(sizeof(*group), GFP_KERNEL); - if (!group) - return ERR_PTR(-ENOMEM); - - minor = ida_alloc_max(&vfio.group_ida, MINORMASK, GFP_KERNEL); - if (minor < 0) { - kfree(group); - return ERR_PTR(minor); - } - - device_initialize(&group->dev); - group->dev.devt = MKDEV(MAJOR(vfio.group_devt), minor); - group->dev.class = vfio.class; - group->dev.release = vfio_group_release; - cdev_init(&group->cdev, &vfio_group_fops); - group->cdev.owner = THIS_MODULE; - - refcount_set(&group->drivers, 1); - mutex_init(&group->group_lock); - INIT_LIST_HEAD(&group->device_list); - mutex_init(&group->device_lock); - group->iommu_group = iommu_group; - /* put in vfio_group_release() */ - iommu_group_ref_get(iommu_group); - group->type = type; - BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier); - - return group; -} - -static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group, - enum vfio_group_type type) -{ - struct vfio_group *group; - struct vfio_group *ret; - int err; - - lockdep_assert_held(&vfio.group_lock); - - group = vfio_group_alloc(iommu_group, type); - if (IS_ERR(group)) - return group; - - err = dev_set_name(&group->dev, "%s%d", - group->type == VFIO_NO_IOMMU ? "noiommu-" : "", - iommu_group_id(iommu_group)); - if (err) { - ret = ERR_PTR(err); - goto err_put; - } - - err = cdev_device_add(&group->cdev, &group->dev); - if (err) { - ret = ERR_PTR(err); - goto err_put; - } - - list_add(&group->vfio_next, &vfio.group_list); - - return group; - -err_put: - put_device(&group->dev); - return ret; -} - -static void vfio_device_remove_group(struct vfio_device *device) -{ - struct vfio_group *group = device->group; - struct iommu_group *iommu_group; - - if (group->type == VFIO_NO_IOMMU || group->type == VFIO_EMULATED_IOMMU) - iommu_group_remove_device(device->dev); - - /* Pairs with vfio_create_group() / vfio_group_get_from_iommu() */ - if (!refcount_dec_and_mutex_lock(&group->drivers, &vfio.group_lock)) - return; - list_del(&group->vfio_next); - - /* - * We could concurrently probe another driver in the group that might - * race vfio_device_remove_group() with vfio_get_group(), so we have to - * ensure that the sysfs is all cleaned up under lock otherwise the - * cdev_device_add() will fail due to the name aready existing. - */ - cdev_device_del(&group->cdev, &group->dev); - - mutex_lock(&group->group_lock); - /* - * These data structures all have paired operations that can only be - * undone when the caller holds a live reference on the device. Since - * all pairs must be undone these WARN_ON's indicate some caller did not - * properly hold the group reference. - */ - WARN_ON(!list_empty(&group->device_list)); - WARN_ON(group->notifier.head); - - /* - * Revoke all users of group->iommu_group. At this point we know there - * are no devices active because we are unplugging the last one. Setting - * iommu_group to NULL blocks all new users. - */ - if (group->container) - vfio_group_detach_container(group); - iommu_group = group->iommu_group; - group->iommu_group = NULL; - mutex_unlock(&group->group_lock); - mutex_unlock(&vfio.group_lock); - - iommu_group_put(iommu_group); - put_device(&group->dev); -} - /* * Device objects - create, release, get, put, search */ /* Device reference always implies a group reference */ -static void vfio_device_put_registration(struct vfio_device *device) +void vfio_device_put_registration(struct vfio_device *device) { if (refcount_dec_and_test(&device->refcount)) complete(&device->comp); } -static bool vfio_device_try_get_registration(struct vfio_device *device) +bool vfio_device_try_get_registration(struct vfio_device *device) { return refcount_inc_not_zero(&device->refcount); } @@ -386,139 +227,6 @@ static int vfio_init_device(struct vfio_device *device, struct device *dev, return ret; } -static struct vfio_group *vfio_noiommu_group_alloc(struct device *dev, - enum vfio_group_type type) -{ - struct iommu_group *iommu_group; - struct vfio_group *group; - int ret; - - iommu_group = iommu_group_alloc(); - if (IS_ERR(iommu_group)) - return ERR_CAST(iommu_group); - - ret = iommu_group_set_name(iommu_group, "vfio-noiommu"); - if (ret) - goto out_put_group; - ret = iommu_group_add_device(iommu_group, dev); - if (ret) - goto out_put_group; - - mutex_lock(&vfio.group_lock); - group = vfio_create_group(iommu_group, type); - mutex_unlock(&vfio.group_lock); - if (IS_ERR(group)) { - ret = PTR_ERR(group); - goto out_remove_device; - } - iommu_group_put(iommu_group); - return group; - -out_remove_device: - iommu_group_remove_device(dev); -out_put_group: - iommu_group_put(iommu_group); - return ERR_PTR(ret); -} - -static bool vfio_group_has_device(struct vfio_group *group, struct device *dev) -{ - struct vfio_device *device; - - mutex_lock(&group->device_lock); - list_for_each_entry(device, &group->device_list, group_next) { - if (device->dev == dev) { - mutex_unlock(&group->device_lock); - return true; - } - } - mutex_unlock(&group->device_lock); - return false; -} - -static struct vfio_group *vfio_group_find_or_alloc(struct device *dev) -{ - struct iommu_group *iommu_group; - struct vfio_group *group; - - iommu_group = iommu_group_get(dev); - if (!iommu_group && vfio_noiommu) { - /* - * With noiommu enabled, create an IOMMU group for devices that - * don't already have one, implying no IOMMU hardware/driver - * exists. Taint the kernel because we're about to give a DMA - * capable device to a user without IOMMU protection. - */ - group = vfio_noiommu_group_alloc(dev, VFIO_NO_IOMMU); - if (!IS_ERR(group)) { - add_taint(TAINT_USER, LOCKDEP_STILL_OK); - dev_warn(dev, "Adding kernel taint for vfio-noiommu group on device\n"); - } - return group; - } - - if (!iommu_group) - return ERR_PTR(-EINVAL); - - /* - * VFIO always sets IOMMU_CACHE because we offer no way for userspace to - * restore cache coherency. It has to be checked here because it is only - * valid for cases where we are using iommu groups. - */ - if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY)) { - iommu_group_put(iommu_group); - return ERR_PTR(-EINVAL); - } - - mutex_lock(&vfio.group_lock); - group = vfio_group_find_from_iommu(iommu_group); - if (group) { - if (WARN_ON(vfio_group_has_device(group, dev))) - group = ERR_PTR(-EINVAL); - else - refcount_inc(&group->drivers); - } else { - group = vfio_create_group(iommu_group, VFIO_IOMMU); - } - mutex_unlock(&vfio.group_lock); - - /* The vfio_group holds a reference to the iommu_group */ - iommu_group_put(iommu_group); - return group; -} - -static void vfio_device_group_register(struct vfio_device *device) -{ - mutex_lock(&device->group->device_lock); - list_add(&device->group_next, &device->group->device_list); - mutex_unlock(&device->group->device_lock); -} - -static void vfio_device_group_unregister(struct vfio_device *device) -{ - mutex_lock(&device->group->device_lock); - list_del(&device->group_next); - mutex_unlock(&device->group->device_lock); -} - -static int vfio_device_set_group(struct vfio_device *device, - enum vfio_group_type type) -{ - struct vfio_group *group; - - if (type == VFIO_IOMMU) - group = vfio_group_find_or_alloc(device->dev); - else - group = vfio_noiommu_group_alloc(device->dev, type); - - if (IS_ERR(group)) - return PTR_ERR(group); - - /* Our reference on group is moved to the device */ - device->group = group; - return 0; -} - static int __vfio_register_dev(struct vfio_device *device, enum vfio_group_type type) { @@ -575,35 +283,6 @@ int vfio_register_emulated_iommu_dev(struct vfio_device *device) } EXPORT_SYMBOL_GPL(vfio_register_emulated_iommu_dev); -static struct vfio_device *vfio_device_get_from_name(struct vfio_group *group, - char *buf) -{ - struct vfio_device *it, *device = ERR_PTR(-ENODEV); - - mutex_lock(&group->device_lock); - list_for_each_entry(it, &group->device_list, group_next) { - int ret; - - if (it->ops->match) { - ret = it->ops->match(it, buf); - if (ret < 0) { - device = ERR_PTR(ret); - break; - } - } else { - ret = !strcmp(dev_name(it->dev), buf); - } - - if (ret && vfio_device_try_get_registration(it)) { - device = it; - break; - } - } - mutex_unlock(&group->device_lock); - - return device; -} - /* * Decrement the device reference count and wait for the device to be * removed. Open file descriptors for the device... */ @@ -646,146 +325,12 @@ void vfio_unregister_group_dev(struct vfio_device *device) } EXPORT_SYMBOL_GPL(vfio_unregister_group_dev); -/* - * VFIO Group fd, /dev/vfio/$GROUP - */ -static bool vfio_group_has_iommu(struct vfio_group *group) -{ - lockdep_assert_held(&group->group_lock); - /* - * There can only be users if there is a container, and if there is a - * container there must be users. - */ - WARN_ON(!group->container != !group->container_users); - - return group->container || group->iommufd; -} - -/* - * VFIO_GROUP_UNSET_CONTAINER should fail if there are other users or - * if there was no container to unset. Since the ioctl is called on - * the group, we know that still exists, therefore the only valid - * transition here is 1->0. - */ -static int vfio_group_ioctl_unset_container(struct vfio_group *group) -{ - int ret = 0; - - mutex_lock(&group->group_lock); - if (!vfio_group_has_iommu(group)) { - ret = -EINVAL; - goto out_unlock; - } - if (group->container) { - if (group->container_users != 1) { - ret = -EBUSY; - goto out_unlock; - } - vfio_group_detach_container(group); - } - if (group->iommufd) { - iommufd_ctx_put(group->iommufd); - group->iommufd = NULL; - } - -out_unlock: - mutex_unlock(&group->group_lock); - return ret; -} - -static int vfio_group_ioctl_set_container(struct vfio_group *group, - int __user *arg) -{ - struct vfio_container *container; - struct iommufd_ctx *iommufd; - struct fd f; - int ret; - int fd; - - if (get_user(fd, arg)) - return -EFAULT; - - f = fdget(fd); - if (!f.file) - return -EBADF; - - mutex_lock(&group->group_lock); - if (vfio_group_has_iommu(group)) { - ret = -EINVAL; - goto out_unlock; - } - if (!group->iommu_group) { - ret = -ENODEV; - goto out_unlock; - } - - container = vfio_container_from_file(f.file); - if (container) { - ret = vfio_container_attach_group(container, group); - goto out_unlock; - } - - iommufd = iommufd_ctx_from_file(f.file); - if (!IS_ERR(iommufd)) { - u32 ioas_id; - - ret = iommufd_vfio_compat_ioas_id(iommufd, &ioas_id); - if (ret) { - iommufd_ctx_put(group->iommufd); - goto out_unlock; - } - - group->iommufd = iommufd; - goto out_unlock; - } - - /* The FD passed is not recognized. */ - ret = -EBADFD; - -out_unlock: - mutex_unlock(&group->group_lock); - fdput(f); - return ret; -} - -static const struct file_operations vfio_device_fops; - /* true if the vfio_device has open_device() called but not close_device() */ static bool vfio_assert_device_open(struct vfio_device *device) { return !WARN_ON_ONCE(!READ_ONCE(device->open_count)); } -static int vfio_device_group_use_iommu(struct vfio_device *device) -{ - struct vfio_group *group = device->group; - int ret = 0; - - lockdep_assert_held(&group->group_lock); - - if (WARN_ON(!group->container)) - return -EINVAL; - - ret = vfio_group_use_container(group); - if (ret) - return ret; - vfio_device_container_register(device); - return 0; -} - -static void vfio_device_group_unuse_iommu(struct vfio_device *device) -{ - struct vfio_group *group = device->group; - - lockdep_assert_held(&group->group_lock); - - if (WARN_ON(!group->container)) - return; - - vfio_device_container_unregister(device); - vfio_group_unuse_container(group); -} - static int vfio_device_first_open(struct vfio_device *device, struct iommufd_ctx *iommufd, struct kvm *kvm) { @@ -837,8 +382,8 @@ static void vfio_device_last_close(struct vfio_device *device, module_put(device->dev->driver->owner); } -static int vfio_device_open(struct vfio_device *device, - struct iommufd_ctx *iommufd, struct kvm *kvm) +int vfio_device_open(struct vfio_device *device, + struct iommufd_ctx *iommufd, struct kvm *kvm) { int ret = 0; @@ -854,8 +399,8 @@ static int vfio_device_open(struct vfio_device *device, return ret; } -static void vfio_device_close(struct vfio_device *device, - struct iommufd_ctx *iommufd) +void vfio_device_close(struct vfio_device *device, + struct iommufd_ctx *iommufd) { mutex_lock(&device->dev_set->lock); vfio_assert_device_open(device); @@ -865,245 +410,6 @@ static void vfio_device_close(struct vfio_device *device, mutex_unlock(&device->dev_set->lock); } -static int vfio_device_group_open(struct vfio_device *device) -{ - int ret; - - mutex_lock(&device->group->group_lock); - if (!vfio_group_has_iommu(device->group)) { - ret = -EINVAL; - goto out_unlock; - } - - /* - * Here we pass the KVM pointer with the group under the lock. If the - * device driver will use it, it must obtain a reference and release it - * during close_device. - */ - ret = vfio_device_open(device, device->group->iommufd, - device->group->kvm); - -out_unlock: - mutex_unlock(&device->group->group_lock); - return ret; -} - -static void vfio_device_group_close(struct vfio_device *device) -{ - mutex_lock(&device->group->group_lock); - vfio_device_close(device, device->group->iommufd); - mutex_unlock(&device->group->group_lock); -} - -static struct file *vfio_device_open_file(struct vfio_device *device) -{ - struct file *filep; - int ret; - - ret = vfio_device_group_open(device); - if (ret) - goto err_out; - - /* - * We can't use anon_inode_getfd() because we need to modify - * the f_mode flags directly to allow more than just ioctls - */ - filep = anon_inode_getfile("[vfio-device]", &vfio_device_fops, - device, O_RDWR); - if (IS_ERR(filep)) { - ret = PTR_ERR(filep); - goto err_close_device; - } - - /* - * TODO: add an anon_inode interface to do this. - * Appears to be missing by lack of need rather than - * explicitly prevented. Now there's need. - */ - filep->f_mode |= (FMODE_PREAD | FMODE_PWRITE); - - if (device->group->type == VFIO_NO_IOMMU) - dev_warn(device->dev, "vfio-noiommu device opened by user " - "(%s:%d)\n", current->comm, task_pid_nr(current)); - /* - * On success the ref of device is moved to the file and - * put in vfio_device_fops_release() - */ - return filep; - -err_close_device: - vfio_device_group_close(device); -err_out: - return ERR_PTR(ret); -} - -static int vfio_group_ioctl_get_device_fd(struct vfio_group *group, - char __user *arg) -{ - struct vfio_device *device; - struct file *filep; - char *buf; - int fdno; - int ret; - - buf = strndup_user(arg, PAGE_SIZE); - if (IS_ERR(buf)) - return PTR_ERR(buf); - - device = vfio_device_get_from_name(group, buf); - kfree(buf); - if (IS_ERR(device)) - return PTR_ERR(device); - - fdno = get_unused_fd_flags(O_CLOEXEC); - if (fdno < 0) { - ret = fdno; - goto err_put_device; - } - - filep = vfio_device_open_file(device); - if (IS_ERR(filep)) { - ret = PTR_ERR(filep); - goto err_put_fdno; - } - - fd_install(fdno, filep); - return fdno; - -err_put_fdno: - put_unused_fd(fdno); -err_put_device: - vfio_device_put_registration(device); - return ret; -} - -static int vfio_group_ioctl_get_status(struct vfio_group *group, - struct vfio_group_status __user *arg) -{ - unsigned long minsz = offsetofend(struct vfio_group_status, flags); - struct vfio_group_status status; - - if (copy_from_user(&status, arg, minsz)) - return -EFAULT; - - if (status.argsz < minsz) - return -EINVAL; - - status.flags = 0; - - mutex_lock(&group->group_lock); - if (!group->iommu_group) { - mutex_unlock(&group->group_lock); - return -ENODEV; - } - - /* - * With the container FD the iommu_group_claim_dma_owner() is done - * during SET_CONTAINER but for IOMMFD this is done during - * VFIO_GROUP_GET_DEVICE_FD. Meaning that with iommufd - * VFIO_GROUP_FLAGS_VIABLE could be set but GET_DEVICE_FD will fail due - * to viability. - */ - if (vfio_group_has_iommu(group)) - status.flags |= VFIO_GROUP_FLAGS_CONTAINER_SET | - VFIO_GROUP_FLAGS_VIABLE; - else if (!iommu_group_dma_owner_claimed(group->iommu_group)) - status.flags |= VFIO_GROUP_FLAGS_VIABLE; - mutex_unlock(&group->group_lock); - - if (copy_to_user(arg, &status, minsz)) - return -EFAULT; - return 0; -} - -static long vfio_group_fops_unl_ioctl(struct file *filep, - unsigned int cmd, unsigned long arg) -{ - struct vfio_group *group = filep->private_data; - void __user *uarg = (void __user *)arg; - - switch (cmd) { - case VFIO_GROUP_GET_DEVICE_FD: - return vfio_group_ioctl_get_device_fd(group, uarg); - case VFIO_GROUP_GET_STATUS: - return vfio_group_ioctl_get_status(group, uarg); - case VFIO_GROUP_SET_CONTAINER: - return vfio_group_ioctl_set_container(group, uarg); - case VFIO_GROUP_UNSET_CONTAINER: - return vfio_group_ioctl_unset_container(group); - default: - return -ENOTTY; - } -} - -static int vfio_group_fops_open(struct inode *inode, struct file *filep) -{ - struct vfio_group *group = - container_of(inode->i_cdev, struct vfio_group, cdev); - int ret; - - mutex_lock(&group->group_lock); - - /* - * drivers can be zero if this races with vfio_device_remove_group(), it - * will be stable at 0 under the group rwsem - */ - if (refcount_read(&group->drivers) == 0) { - ret = -ENODEV; - goto out_unlock; - } - - if (group->type == VFIO_NO_IOMMU && !capable(CAP_SYS_RAWIO)) { - ret = -EPERM; - goto out_unlock; - } - - /* - * Do we need multiple instances of the group open? Seems not. - */ - if (group->opened_file) { - ret = -EBUSY; - goto out_unlock; - } - group->opened_file = filep; - filep->private_data = group; - ret = 0; -out_unlock: - mutex_unlock(&group->group_lock); - return ret; -} - -static int vfio_group_fops_release(struct inode *inode, struct file *filep) -{ - struct vfio_group *group = filep->private_data; - - filep->private_data = NULL; - - mutex_lock(&group->group_lock); - /* - * Device FDs hold a group file reference, therefore the group release - * is only called when there are no open devices. - */ - WARN_ON(group->notifier.head); - if (group->container) - vfio_group_detach_container(group); - if (group->iommufd) { - iommufd_ctx_put(group->iommufd); - group->iommufd = NULL; - } - group->opened_file = NULL; - mutex_unlock(&group->group_lock); - return 0; -} - -static const struct file_operations vfio_group_fops = { - .owner = THIS_MODULE, - .unlocked_ioctl = vfio_group_fops_unl_ioctl, - .compat_ioctl = compat_ptr_ioctl, - .open = vfio_group_fops_open, - .release = vfio_group_fops_release, -}; - /* * Wrapper around pm_runtime_resume_and_get(). * Return error code on failure or 0 on success. @@ -1699,7 +1005,7 @@ static int vfio_device_fops_mmap(struct file *filep, struct vm_area_struct *vma) return device->ops->mmap(device, vma); } -static const struct file_operations vfio_device_fops = { +const struct file_operations vfio_device_fops = { .owner = THIS_MODULE, .release = vfio_device_fops_release, .read = vfio_device_fops_read, @@ -1709,121 +1015,6 @@ static const struct file_operations vfio_device_fops = { .mmap = vfio_device_fops_mmap, }; -/** - * vfio_file_iommu_group - Return the struct iommu_group for the vfio group file - * @file: VFIO group file - * - * The returned iommu_group is valid as long as a ref is held on the file. This - * returns a reference on the group. This function is deprecated, only the SPAPR - * path in kvm should call it. - */ -struct iommu_group *vfio_file_iommu_group(struct file *file) -{ - struct vfio_group *group = file->private_data; - struct iommu_group *iommu_group = NULL; - - if (!IS_ENABLED(CONFIG_SPAPR_TCE_IOMMU)) - return NULL; - - if (!vfio_file_is_group(file)) - return NULL; - - mutex_lock(&group->group_lock); - if (group->iommu_group) { - iommu_group = group->iommu_group; - iommu_group_ref_get(iommu_group); - } - mutex_unlock(&group->group_lock); - return iommu_group; -} -EXPORT_SYMBOL_GPL(vfio_file_iommu_group); - -/** - * vfio_file_is_group - True if the file is usable with VFIO aPIS - * @file: VFIO group file - */ -bool vfio_file_is_group(struct file *file) -{ - return file->f_op == &vfio_group_fops; -} -EXPORT_SYMBOL_GPL(vfio_file_is_group); - -/** - * vfio_file_enforced_coherent - True if the DMA associated with the VFIO file - * is always CPU cache coherent - * @file: VFIO group file - * - * Enforced coherency means that the IOMMU ignores things like the PCIe no-snoop - * bit in DMA transactions. A return of false indicates that the user has - * rights to access additional instructions such as wbinvd on x86. - */ -bool vfio_file_enforced_coherent(struct file *file) -{ - struct vfio_group *group = file->private_data; - struct vfio_device *device; - bool ret = true; - - if (!vfio_file_is_group(file)) - return true; - - /* - * If the device does not have IOMMU_CAP_ENFORCE_CACHE_COHERENCY then - * any domain later attached to it will also not support it. If the cap - * is set then the iommu_domain eventually attached to the device/group - * must use a domain with enforce_cache_coherency(). - */ - mutex_lock(&group->device_lock); - list_for_each_entry(device, &group->device_list, group_next) { - if (!device_iommu_capable(device->dev, - IOMMU_CAP_ENFORCE_CACHE_COHERENCY)) { - ret = false; - break; - } - } - mutex_unlock(&group->device_lock); - return ret; -} -EXPORT_SYMBOL_GPL(vfio_file_enforced_coherent); - -/** - * vfio_file_set_kvm - Link a kvm with VFIO drivers - * @file: VFIO group file - * @kvm: KVM to link - * - * When a VFIO device is first opened the KVM will be available in - * device->kvm if one was associated with the group. - */ -void vfio_file_set_kvm(struct file *file, struct kvm *kvm) -{ - struct vfio_group *group = file->private_data; - - if (!vfio_file_is_group(file)) - return; - - mutex_lock(&group->group_lock); - group->kvm = kvm; - mutex_unlock(&group->group_lock); -} -EXPORT_SYMBOL_GPL(vfio_file_set_kvm); - -/** - * vfio_file_has_dev - True if the VFIO file is a handle for device - * @file: VFIO file to check - * @device: Device that must be part of the file - * - * Returns true if given file has permission to manipulate the given device. - */ -bool vfio_file_has_dev(struct file *file, struct vfio_device *device) -{ - struct vfio_group *group = file->private_data; - - if (!vfio_file_is_group(file)) - return false; - - return group == device->group; -} -EXPORT_SYMBOL_GPL(vfio_file_has_dev); - /* * Sub-module support */ @@ -1943,11 +1134,6 @@ int vfio_set_irqs_validate_and_prepare(struct vfio_irq_set *hdr, int num_irqs, } EXPORT_SYMBOL(vfio_set_irqs_validate_and_prepare); -static bool vfio_device_has_container(struct vfio_device *device) -{ - return device->group->container; -} - /* * Pin contiguous user pages and return their associated host pages for local * domain only. @@ -2069,55 +1255,6 @@ EXPORT_SYMBOL(vfio_dma_rw); /* * Module/class support */ -static char *vfio_devnode(struct device *dev, umode_t *mode) -{ - return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev)); -} - -static int __init vfio_group_init(void) -{ - int ret; - - ida_init(&vfio.group_ida); - mutex_init(&vfio.group_lock); - INIT_LIST_HEAD(&vfio.group_list); - - ret = vfio_container_init(); - if (ret) - return ret; - - /* /dev/vfio/$GROUP */ - vfio.class = class_create(THIS_MODULE, "vfio"); - if (IS_ERR(vfio.class)) { - ret = PTR_ERR(vfio.class); - goto err_group_class; - } - - vfio.class->devnode = vfio_devnode; - - ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK + 1, "vfio"); - if (ret) - goto err_alloc_chrdev; - return 0; - -err_alloc_chrdev: - class_destroy(vfio.class); - vfio.class = NULL; -err_group_class: - vfio_container_cleanup(); - return ret; -} - -static void vfio_group_cleanup(void) -{ - WARN_ON(!list_empty(&vfio.group_list)); - ida_destroy(&vfio.group_ida); - unregister_chrdev_region(vfio.group_devt, MINORMASK + 1); - class_destroy(vfio.class); - vfio.class = NULL; - vfio_container_cleanup(); -} - static int __init vfio_init(void) { int ret; -- 2.34.1